Peale's Dolphin

Lagenorhynchus australis
Black-chinned dolphin, Peale's black-chinned dolphin, Peale’s Porpoise and Southern white-sided dolphin
Peale’s dolphins are small to medium sized dolphins that live in the sea around Tierra del Fuego, South America. Adults are black to dark gray, with lighter shading on their flanks. They are coastal dolphins and can often be seen swimming near the coastline in groups and hunting for prey. The oldest Peale’s dolphin recorded in the wild was the age of 13.
Unknown

population size

13 yrs

Life span

115 kg

Weight

2 m

Length

Disrtibution

Peale’s dolphin occurs only near the southernmost tip of South America and off Santiago, Chile, and northern Argentina. It is commonly seen near the Falkland Islands (Malvinas) and at Burdwood Bank, south of the Falklands. Sightings have been reported in the South Pacific around Palmerston Atoll, but this is outside the usual range and possibly represents a new, undescribed species. These dolphins inhabit open coastal waters above shallow continental shelves, bays, inlets, channels, near islands and in fjord openings. Although found as deep as 300 meters, they prefer shallower coastal waters, particularly associated with beds of kelp.

Habits and lifestyle

Peale’s dolphins are gregarious, swimming in groups from 2 to 13 individuals, with most sightings being of groups that have 2 to 4 members. Groups with as many as 100 members have been seen, more often during January and February. The larger groups tend to divide up into sub-groups. The Peale’s dolphin surfaces three to four times every minute and dives for one to 130 seconds, with the average dive being less than 60 seconds. They display many different kinds of behavior. While swimming they can be seen jumping, spinning, humping and tailslapping, the latter being thought to aid foraging by sending fish towards other dolphins.

group name

pod, school, herd

Diet and nutrition

This species is carnivore (piscivore and molluscivore). The diet of Peale’s dolphin includes: Argentine shrimp, squid, Argentine hake, Kingklip fish, southern cod, hagfish, red octopus Pantagonian grenadier, herring, mackerel, anchovies, capelin, crustaceans and whelks (gastropods).

Diet

Mating habits

Not much is known about the Peale’s dolphin’s mating behavior or its biology, as it is seldom found stranded. Births are usually between the southern hemisphere’s spring and autumn but can be as early as October. Usually for species within the same genus (Lagenorynchus) the gestation period is ten to twelve months, with females bearing one calf at a time. The mother nurses her calf for about 18 months, although it may remain dependent for a further 6 months. It is unknown at what age these animals reach reproductive maturity.

Reproduction season

between the southern hemisphere’s spring and autumn but can be as early as October

Pregnancy duration

10-12 months

Independent age

24 months
cow

female name

bull

male name

calf

baby name

1 calf

baby carrying

Population

Population status

ne
dd
lc
nt
vu
en
cr
ew
ex

Population threats

Since the 1970s these dolphins have been heavily exploited for crab bait. This practice still takes place in Chile, although less often than previously. They also sometimes drown in gillnets, and a small number are caught in the anti-predator nets near salmon pens in Chile. Further threats include organochlorine pollution, as well as threats to the forests of kelp on which they depend.

Population number

According to IUCN, Peale’s dolphin is the most common cetacean throughout its range but no overall population estimate is available. Currently this species is classified as Data Deficient on the IUCN Red List.

Ecological niche

Not much known about Peale’s dolphin’s effect on the oceanic ecosystem. However, they may affect predator populations, as items of prey.

Fun facts for kids

  1. Peale’s dolphins can be mistaken for dusky dolphins in much of their range.
  2. Peale’s dolphins will often follow in a boat’s wake, but turning off the propeller seems to lead to loss of interest.
  3. These dolphins are often observed associating with other species of dolphin, particularly Commerson’s dolphin.
  4. In Spanish Peale’s dolphin was previously called llampa or in Chile, tunina. Now it is known as delfin austral or Southern dolphin in both Chile and Argentina.
  5. In groups, Peale’s dolphin generally engages in what is called “starburst” or "flower" feeding, encircling prey and forming a large group to then feast. This is done mostly within the kelp beds.

References

  1. Peale's Dolphin Wikipedia article
    https://en.wikipedia.org/wiki/Peale%27s_dolphin
  2. Peale's Dolphin on The IUCN Red List site
    http://www.iucnredlist.org/details/11143/0